High-breakdown, high-gain InAlAs/InGaAsP quantum-well HEMTs

An investigation was conducted of the DC and RF characteristics of InAlAs/InGaAsP quantum-well channel HEMTs. An extrinsic transconductance as high as 210 mS/mm was obtained for a gate length of 1.0 mu m. The HEMTs showed excellent drain-source and gate-drain breakdown characteristics and a very small output conductance of less than 2 mS/mm, resulting in a very high DC voltage gain of greater than 100. The maximum available gain (MAG) was measured to be as high as 14.5 dB at 20 GHz, which corresponds to an extrapolated f/sub max/ of 105 GHz.>